Which lead is +/-?

Just got some 6.5" door speakers but they don't have anything to identify which one is positive and which is negative? Do I just hook them up and see which is which or is the positive on the left always or something like that?

Re: Which lead is +/-?

test it with a set of wires and a 9v battery...connect the speaker wires to each terminal then touch the battery + to the + on the battery and the same for the -...if the speaker cone move out you have it correctly....if it moves in towards itself you have it backwards....then label them...